同根派生 英汉例句Sapwood is the lighter colored wood growing from inside the bark to the heartwood.邊材色澤較淺，是從樹皮到新材之間的木質部分。Heartwood is the mature wood, which is often darker, extending from the sapwood to the pith.心材通常是成熟的木材部分，通常色澤較暗，範圍從邊材一直到髓心。